2018-11-22 10:25:00

by Myungho Jung

Subject: [PATCH] fuse: Add bad inode check in fuse_destroy_inode()

make_bad_inode() sets inode->i_mode to S_IFREG if I/O error is detected
in fuse_do_getattr()/fuse_do_setattr(). If the inode is not a regular
file, write_files and queued_writes in fuse_inode are not initialized
and have NULL or invalid pointers written by other members in a union.
So, list_empty() returns false in fuse_destroy_inode(). Add
is_bad_inode() to check if make_bad_inode() was called.

Reported-by: [email protected]
Signed-off-by: Myungho Jung <[email protected]>
---
fs/fuse/inode.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/fuse/inode.c b/fs/fuse/inode.c
index 0b94b23b02d4..073865371f9b 100644
--- a/fs/fuse/inode.c
+++ b/fs/fuse/inode.c
@@ -115,7 +115,7 @@ static void fuse_i_callback(struct rcu_head *head)
static void fuse_destroy_inode(struct inode *inode)
{
struct fuse_inode *fi = get_fuse_inode(inode);
- if (S_ISREG(inode->i_mode)) {
+ if (S_ISREG(inode->i_mode) && !is_bad_inode(inode)) {
WARN_ON(!list_empty(&fi->write_files));
WARN_ON(!list_empty(&fi->queued_writes));
}
--
2.17.1

2018-11-23 07:47:32

by Miklos Szeredi

Subject: Re: [PATCH] fuse: Add bad inode check in fuse_destroy_inode()

On Thu, Nov 22, 2018 at 12:18 AM Myungho Jung <[email protected]> wrote:
>
> make_bad_inode() sets inode->i_mode to S_IFREG if I/O error is detected
> in fuse_do_getattr()/fuse_do_setattr(). If the inode is not a regular
> file, write_files and queued_writes in fuse_inode are not initialized
> and have NULL or invalid pointers written by other members in a union.
> So, list_empty() returns false in fuse_destroy_inode(). Add
> is_bad_inode() to check if make_bad_inode() was called.
>
> Reported-by: [email protected]
> Signed-off-by: Myungho Jung <[email protected]>

Thanks, applied.

Miklos